Self sharpening plow point



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T. 00X, SELF SHARPENING PLOW POINAT. 7 No. 305,800. Patented Sept. .30, 1884.

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T. COX.

SELF SHARPENING PLOW POINT. No. 305,800, Patented Sept. 30, 1884.

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UNITED STATES rs tries.

ONE-HALF TO JOHN R. NICHOLSON, OF SAME PLACE.

SELF-SH A RPENING PLOW-POINT.

GPECIPIGATKON forming part of Letters Patent No. 305,800, dated September 30, 1884. A Application filed April 15, 1884. (No model.)

To (Jr/Z5 whom it may concern:

Be it knownfrhat I, THOMAS Cox, a citizen of the United States, residing at Dover, in the county of Kent and State of Delaware, have invented a new and useful Improvement in Self-Sharpening Flows, of which the following is a specification;

In an applicationfiled by me in the Patent Ofiice on the 13th day of February, 1884, I have described and claimed a self-sharpening plowshare provided with a reversible cuttingedge attached to the share in such a manner as to be capable of being easily reversed and secured in place without the use of bolts or other clamping devices.

My present invention consists in certain improvements in the mode of fastening the outting-edge to the share described. in the said application, and in an improved reversible plow-point, which may be applied to any form of plow and used either with my reversible cutting-edge or alone, all of which improvements I shall explain by reference to the accompanying drawings, in which- Figure 1 is a plan or top view of a plowshare provided with my reversible cutting edge and point. Fig. 2- is a side view of the same. Fig. 3 is a section of the plow-point on the plane 3 3 of Fig. ,1. Fig. 4; is a section on the plane a 4. Fig. 5 is a section on the plane 5 5. Fig. dis a back view of the cuttingedge. Fig. 7 is avicw in perspective showing the construction of my improved reversible plowpoint,the point being removed from the share.

A represents the share cast in such a shape as to receive the reversiblewedge-shaped cutting-edge 6, upon the back of which is cast a tongue or rib, D,which is mortised into a slot cast-in the share to receive it, this construction being described in the application already filed by me above referred to.

My present improvement in the cutting-edge consists, first, in casting a projection or enlargement, D, on one side of the tongue D, and also casting a corresponding recess in the share for this enlargement D to fit into. The object ofi this enlargement is to prevent slipping of the tongueD lengthwise in the slot toward the heel of the plow, and take the strain off the pins through the holes d d, by

which the cutting-edge is held in the share.

I have shown this enlargement cast in the form of a square projection on the top of the tongue D; but it may be cast upon the bottom or back of the tongue, if desired, and may be of any desired thickness and shape. I

In order to prevent grass from collecting at the front end of the cutting-edge where it joins the share, I cast the rear end of the plow-point in such a shape as to leave a shoulder, G, projecting over the edge of the cutting-edge, as is clearly seen in Fig. 4, which prevents the crack between the cutting-edge and share becoming clogged in any way.

My'improved reversible point consists of a tapering projection, B, cast upon the share or mold-board, and provided with the tongues or ribs 1) I), cast upon each side thereof, the cap or point proper, B, having cast in it a recess exactly corresponding in shape to the part B with its projecting ribs. A square hole or notch, b, is cast on both sides of the point B, as shown, to receive a pin or nail which passes through a corresponding notch in the rib b on only one side of the part B, through 7 5 which slot a nail is driven in order to fasten the point B to the share. To reverse the point B, it is only necessaryto drive out the nail, remove the point, and turn it over,when it will fit equally well upon the part B,where it may be secured again by means of a nail. By this construction the larger and stronger projection B is cast upon the share, while the jaws which are comparatively weak and liable to break first form partof the cap-point,which insures the breaking of the said cap-point first, this being the great advantage of my invention.

I am aware that a tapering projection has been cast on the share and provided with re- 0 cesses before; but this construction I do not claim.

What I claim as my invention, and desire to secure by Letters Patent, is-

1. The plowshare A, provided with the reversible outtingedge C, said cutting-edge having a tongue or rib, D,east upon its back,and also the projection or enlargement D,andmortised into the slot-in the share, as shown and describethwhereby the cutting-edge is rigidly IOO attached to the share and prevented from slipping lengthwise in the share.

side thereof the tongues b I), and the cap-point B, provided with two recessed jaws, which fit on each side of the shank B, whereby the said I 5 cap-point is made the weaker part, and the point is adapted to have the greatest possible strength,substantially as shown and described.

Signed this 12th day of April, 1884.

THOMAS COX.

Witnesses:

Tnos. S. CLARK, JOHN S. J ESTER. 

